NANO-OPTICS Fundamentals,Experimental
Methods,andApplications
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SABUTHOMAS YVESGROHENS
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NANDAKUMARKALARIKKAL
JEMYJAMES
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Contributors
HarithAhmad
PhotonicsResearchCenter,UniversityofMalaya,KualaLumpur,Malaysia
StuartBowden
QuantumEnergyforSustainableSolarTechnology(QESST)EngineeringResearchCenter, ArizonaStateUniversity,Tempe,AZ,UnitedStates
DermotBrabazon
I-Form,AdvancedManufacturingResearchCentre,&AdvancedProcessingTechnology ResearchCentre,SchoolofMechanicalandManufacturingEngineering,DublinCity University,Dublin,Ireland
JenuV.Chacko
LaboratoryforOpticalandComputationalInstrumentation(LOCI),UniversityofWisconsinat Madison,Madison,WI,UnitedStates
BaluChandra
InternationalSchoolofPhotonics,CochinUniversityofScienceandTechnology,Cochin, Kerala,India
JudithM.Dawes
MQPhotonicsResearchCenter,DepartmentofPhysicsandAstronomy,MacquarieUniversity, Sydney,NSW,Australia
JoydeepDutta
FunctionalMaterialsdivision,MaterialsandNano-PhysicsDepartment,ICTSchool,KTH RoyalInstituteofTechnology,Stockholm,Sweden
NitinEapen
InternationalandInterUniversityCentreforNanoscienceandNanotechnology,Mahatma GandhiUniversity,Kottayam,Kerala,India
KarstenFleischer
I-Form,AdvancedManufacturingResearchCentre,&AdvancedProcessingTechnology ResearchCentre,SchoolofMechanicalandManufacturingEngineering,DublinCity University,Dublin,Ireland
StephenGoodnick
QuantumEnergyforSustainableSolarTechnology(QESST)EngineeringResearchCenter, ArizonaStateUniversity,Tempe,AZ,UnitedStates
YvesGrohens
FRECNRS3744,IRDL,UniversityofSouthernBrittany,Lorient,France
BanshiD.Gupta
PhysicsDepartment,IndianInstituteofTechnologyDelhi,NewDelhi,India
SulaimanWadiHarun
DepartmentofElectricalEngineering,FacultyofEngineering,UniversityofMalaya,Kuala Lumpur,Malaysia
ChristianaHonsberg
QuantumEnergyforSustainableSolarTechnology(QESST)EngineeringResearchCenter, ArizonaStateUniversity,Tempe,AZ,UnitedStates
JemyJames
FRECNRS3744,IRDL,UniversityofSouthernBrittany,Lorient,France;Internationaland InterUniversityCentreforNanoscienceandNanotechnology,MahatmaGandhiUniversity, Kottayam,Kerala,India
JerryJose
InternationalandInterUniversityCentreforNanoscienceandNanotechnology,Mahatma GandhiUniversity,Kottayam,Kerala,India
BlessyJoseph
FRECNRS3744,IRDL,UniversityofSouthernBrittany,Lorient,France;Internationaland InterUniversityCentreforNanoscienceandNanotechnology,MahatmaGandhiUniversity, Kottayam,Kerala,India
NandakumarKalarikkal
SchoolofPureandAppliedPhysics;InternationalandInterUniversityCentreforNanoscience andNanotechnology,MahatmaGandhiUniversity,Kottayam,Kerala,India
ChanghyoupLee
InstituteofTheoreticalSolidStatePhysics,KarlsruheInstituteofTechnology,Karlsruhe, Germany
Kwang-GeolLee DepartmentofPhysics,HanyangUniversity,Seoul,Korea
JubyAlphonsaMathew
InternationalandInterUniversityCentreforNanoscienceandNanotechnology,Mahatma GandhiUniversity,Kottayam,Kerala,India
EannaMcCarthy
I-Form,AdvancedManufacturingResearchCentre,&AdvancedProcessingTechnology ResearchCentre,SchoolofMechanicalandManufacturingEngineering,DublinCity University,Dublin,Ireland
WaleedSolimanMohammed
CenterofResearchinOptoelectronics,CommunicationandControlSystems(BU-CROCCS), SchoolofEngineering,BangkokUniversity,PathumThani,Thailand
RajeshV.Nair
DepartmentofPhysics,IndianInstituteofTechnologyRopar,Rupnagar,Punjab,India
ParvathyNancy
SchoolofPureandAppliedPhysics;InternationalandInterUniversityCentreforNanoscience andNanotechnology,MahatmaGandhiUniversity,Kottayam,Kerala,India
AnishaPathak
PhysicsDepartment,IndianInstituteofTechnologyDelhi,NewDelhi,India
HazliRafisAbdulRahim
DepartmentofElectricalEngineering,FacultyofEngineering,UniversityofMalaya,Kuala Lumpur;UniversitiTeknikalMalaysiaMelaka,Melaka,Malaysia
SitiAisyahReduan
PhotonicsResearchCenter,UniversityofMalaya,KualaLumpur,Malaysia
CarstenRockstuhl
InstituteofTheoreticalSolidStatePhysics;InstituteofNanotechnology,KarlsruheInstituteof Technology,Karlsruhe,Germany
SwastiSaxena
DepartmentofAppliedPhysics,SardarVallaBhaiNationalInstituteofTechnology,Surat, Gujarat,India
VivekSemwal
PhysicsDepartment,IndianInstituteofTechnologyDelhi,NewDelhi,India
AshinShaji
InstituteofPhysics,SlovakAcademyofSciences,Bratislava,Slovakia
SitharaP.Sreenilayam
I-Form,AdvancedManufacturingResearchCentre,&AdvancedProcessingTechnology ResearchCentre,SchoolofMechanicalandManufacturingEngineering,DublinCity University,Dublin,Ireland
AnkitKumarSrivastava
SchoolofAppliedNaturalScience,AdamaScienceandTechnologyUniversity,Adama,Ethiopia
MarkTame
DepartmentofPhysics,StellenboschUniversity,Stellenbosch,SouthAfrica
KavintheranThambiratnam
PhotonicsResearchCenter,UniversityofMalaya,KualaLumpur,Malaysia
SiddharthThokchom
NationalInstituteofTechnologyManipur,Imphal,India
SabuThomas SchoolofChemicalSciences;InternationalandInterUniversityCentreforNanoscienceand Nanotechnology,MahatmaGandhiUniversity,Kottayam,Kerala,India
ZianCheakTiu
PhotonicsResearchCenter,UniversityofMalaya,KualaLumpur,Malaysia
JijoP.Ulahannan
DepartmentofPhysics,GovernmentCollege,Kasaragod,Kerala,India
GuillaumeVignaud
FRECNRS3744,IRDL,UniversityofSouthernBrittany,Lorient,France
Fromnature:Optics,nanotechnology, andnano-optics
AshinShajia,JemyJamesb,c,ParvathyNancyc,d aInstituteofPhysics,SlovakAcademyofSciences,Bratislava,Slovakia bFRECNRS3744,IRDL,UniversityofSouthernBrittany,Lorient,France cInternationalandInterUniversityCentreforNanoscienceandNanotechnology,MahatmaGandhiUniversity,Kottayam, Kerala,India dSchoolofPureandAppliedPhysics,MahatmaGandhiUniversity,Kottayam,Kerala,India
1.Introduction
Nanomaterialsareabundantinnature,sinceeverythinginourworldiscomposedofvery smallparticles.Asaresult,nanotechnologyisalwaysinspiredbynatureandnaturalphenomena.Thepropertiesofthematerialscreatedbynaturethroughevolutionaryprocessesarehighlyefficientoroptimal,hencetheuseofnaturalmaterialsdirectlyinthe developmentofnanotechnologyisofgreatimportance.Nowscientistshaveaclearidea ofhowtocreatenanoscalematerialswithuniquepropertiesthatneverexistedbefore. Productsusingnanomaterialsarenowavailableinthemarket,suchasnanoscalesilver asanantibacterial [1],sunscreenwithnanoscaletitaniumdioxidethatpreventssunburn [2],applicationinthefieldofelectronicsasinbatteries,targeteddrugdelivery,nanofilms forcoatings,waterfiltration,etc. [3] Molecular-levelmanipulationistheultimatebaseof nanotechnology,butthatdoesn’tmeanthatthisfieldofsciencealwaysdealsonlywith artificialmaterials.
Innature,moleculesorganizethemselvesintocomplexstructuresthatcouldsupport life,similartothepresentnanotechnologythatweareusedto.Natureconstructseverythingatombyatom,andunderstandingthebasicprincipleofnaturalsystemswillhelp nanoscientiststodesignartificialnanomaterials.Forexample,oncologistsarelookinginto nanotechnologyasapotentialwaytotreatcancerwithtargeteddrugdeliverybytheuse ofnanomedicine [4].Theinspirationforthisisfromthevirusesthatseekoutaspecific typeofcelltoattackinalivingorganism.Similarly,opticallytransparentmaterialshave beenimprovedbyimitatingthenanostructuresfoundinthewingsofinsects.Finding inspirationfromnature’snanotechisbecomingbigbusinessnowadays.
Nano-opticsornanophotonicshasbecomeaserioustopicofresearchoverthepast decades.Theinteractionoflightwithnanometer-scaleparticleshasdevelopedintoanew andseparatebranchfromconventionalphotonicsresearchtopicsduetoitsmassivepresenceinthenaturalworldandalsofromanapplicationpointofview.Onthenanometer
scale,materialsincludingmetals,semiconductors,dielectrics,andpolymersexhibitinterestingproperties,especiallyopticalproperties [5].Particlesthatcomeunderasizerangeof nanometersshowspecialphenomenathatarenotpredictableasintheirbulkcounterparts.Makinguseofthesepropertiesofthenanoparticlesinthefieldofopticsandphotonicsisthecoreofnanophotonics [6].Themajoraimofthischapteristogiveabrief introductiontothepresenceofnanotechnologyandnanophotonicsinthenaturalworld ratherthantheartificiallycreatednanouniverse.Withoutgoingintodeepertheoretical aspects,thischapterpresentsanoverallpictureoftheinfluenceandexistenceofnanotechnologyinnature.
2.Natureandoptics
Innature,opticalphenomenaareobservableasaresultoftheinteractionofmatterand light;interactionsoflightfromthesunandmoonwithparticlesintheatmosphere, clouds,water,dust,etc.arethereasonforsomeofthecommonnaturalopticalphenomenonlikemiragesandrainbows(Fig.1).Manyofthesenaturalphenomenainnaturearise fromtheopticalpropertiesoftheatmosphereandduetothepresenceofotherobjectsin natureorsometimesevenduetothevisualillusioncreatedbythehumaneye,suchas entopticphenomena [7]
Theparticleandwavenatureofthelightalsoinfluencesthiskindofphenomenon. Somearequitedelicateandnoticeableonlybyprecisescientificmeasuringinstruments. Oneofthenotableobservationsisthebendingoflightfromastarbythesun,observed duringthetimeofthesolareclipse.Thisdemonstratesthatspaceiscurved,aspredictedby Einsteininhistheoryofrelativity.Mostopticalphenomenacanbeexplainedonthebasis oftheclassicalelectromagneticexplanationoflight.Butinpracticalapplications,a completelyelectromagneticdescriptionoflightisoftendifficulttoapplyinpractice. Soforpracticalapplications,opticsisusuallydemonstratedusingsimplifiedmodels,like geometricoptics,thattreatlightasacollectionofraysthattravelinastraightlineand bendfromasurfacewhentheypassthroughorreflectfromit.Waveopticsorphysical opticsisamoreinclusivemodeloflight,whichexplainsthewavenatureofsuchphenomenaasdiffractionandinterference,whichcannotbeexplainedusinggeometric optics.
Basedonthehistoryoflightinnature,thefirstacceptedmodeltoexplainthenature oflightistheray-basedmodeloflight,andlateron,thewavemodeloflight.Theintroductionoftheelectromagnetictheoryinthe19thcenturyledtotherediscoveryoflight wavesaselectromagneticradiation.Evenso,therearesomephenomenainnaturethat canbeexplainedonlybyconsideringthefactthatlighthasbothwavelikeandparticlelikenature(dualnatureoflight),effectsthatrequirequantummechanicalexplanations. Quantumopticsisthefieldofsciencethatdealswiththeapplicationofquantummechanicstoopticalsystems.Whenconsideringtheparticle-likenatureoflight,lightis
Fig.1 Someofthecommonopticalphenomenahappeninginnature:(A)doublerainbowand supernumeraryrainbowsontheinsideoftheprimaryarc;(B)verybrightsundogsinFargo,North Dakota;(C)thereflectionofMountHoodinMirrorLake;(D)a22° haloaroundthesun,asseenin theskyoverAnnapurnaBaseCamp,Annapurna,Nepal. ((A)EricRolphatEnglishWikipedia(https:// commons.wikimedia.org/wiki/File:Double-alaskan-rainbow.jpg ), “Double-alaskan-rainbow, ” sizeand shapeoftheimagebyAshinShaji, https://creativecommons.org/licenses/by-sa/2.5/legalcode ;(D)Anton Yankovyi(https://commons.wikimedia.org/wiki/File:Halo_in_the_Himalayas.jpg ),sizeandshapeofthe imagebyAshinShaji, https://creativecommons.org/licenses/by-sa/4.0/legalcode .)
consideredasacollectionofparticlescalledphotons.Opticalscienceisanimportantand applicablefieldofscienceinmanyrelateddisciplineslikeastronomy,photography,variousengineeringfields,andespeciallyinmedicalfieldslikeoptometryandophthalmology.Practicalimplementationofopticsisfoundineverydaylifeandinavarietyof technologiesliketelescopes,mirrors,lenses,microscopes,lasers,opticalfibers,etc.
Mostcolorsinnatureoriginateduetoselectiveadsorptionresultingfromthepigmentationembeddedinthebodyorsurfaceofanobject.However,acertainrangeofintense andbrightcontrastcolorsresultfromtheinteractionoflightwithnano-andmicrostructures,whichleadstotheappearanceofcolorbycoherentscattering,interference,and diffractionwithoutanyabsorption.Thesecolorsarecommonlyknownas“structural colors” [8].Thestructuresthathelptomodulatelightleadingtostructuralcolorsarepart ofthefamilyofphotonicstructuresinnature.
Photonicstructurescanbedefinedasregularstructureswithperiodicitiesmatching withtheorderofthewavelengthofthelight [9].Structuralcolorshavebeenahottopic ofresearchforcenturies,andtheinvolvementofmicro-andnanostructuresinthemwas introducedbyHooke(1665),Newton(1704),andLordRayleigh(1917) [8].Thefirst everimagingandadetailedstudyofstructuralelementsthatinducestructuralcolorswere suggestedbyAndersonandRichards [10] aftertheintroductionoftheelectronmicroscope.Theinterestinnaturalstructuralcolorswasfoundtoincreaseduetothefast growthinthefieldofopticalspectroscopyandscanning/transmissionmicroscopy.These spectroscopictechniqueshelptoinvestigatethedetailsofthecomplexnanoandmicrostructureswithuniqueopticalcharacteristicsthatevolvedandexistedsolelyinnaturefor millionsofyears [11].
Opticalissueslikehighreflectivityortransmission,str ongpolarizationoflight, dichroism,spectralfiltering,etc.,canbecontrolledwiththehelpofthenaturalworld sincenatureprovidessolutionsforalltheseintheformofnanostructuresofdifferent morphologicalvarieties.Thus,natureoffersanabundantnumberofroadmapsfor multifunctionalmicro-andnanostructures thatshowoutstandingdynamicanddistinctivecoloration.Thiskindofstructuredmaterialoriginatesasaresultofevolutionover millionsofyearsandinvitestheinterestof scientiststocarryoutdeeperresearchthat maybuildthebasisoffutureopticaldevices.Itcanfindapplicationsinmedicaldiagnostics,communication,informationprocessing,anddeviceswithfunctionalitiesthat cangobeyondthecurrentstage.Therefore,thebiomimeticapproachiscurrentlyahot fieldofscience.Forthepurposeofsolvingcomplexhumanproblems,imitationor copyingthemodels,systems,orsolutions fromnatureisknownasbiomimeticorbiomimicry [12]
3.Nanotechnologyinnature
Nanoscienceandnanotechnologyalwaysfindinspirationfromnature.Somecommon nanostructuresthatarevisibleinnatureincludeinorganicmaterialssuchascarbonaceous soot,clay,organicnaturalthinfilms,andavarietyoforganicnanostructuressuchasproteins,insects,andcrustaceanshells.Thesestructurescausearangeofbehaviorsinnature togetherwiththewettabilityofsurfaces,thebrightnessofbutterflywings,andalsothe adhesivepropertiesofthelizard’sfoot.
Thecolorationofmanyvarietiesofbeetlesandbutterfliesiscreatedbysetsofrigorouslyspacednanoscopicpillars.Fabricatedfromsugarslikechitosan,orproteinslikekeratin,thewidthsofslitsbetweenthepillarsaredesignedtocontrollighttoattaincertain colorsoreffectslikeiridescence.Oneadvantageofthisstrategyisresilience.Pigments tendtobleachwithexposuretolight;however,structuralcolorsarestableforremarkably longperiods.
Astudyofstructuralcolorationinmetallic-bluemarbleberries [13] wherethespecimenscollectedin1974,thathadmaintainedtheircolordespitebeinglongdead.Similarly,alotusleafisanexampleofanengineeredsurfacebecauseofitsphysicaland chemicalconditionsatthemicro-andnanometerscale,abletoprovideaself-cleaning effect.WilhelmBarthlott,aGermanbotanist,isconsideredtobethediscovererofthe Lotuseffect [14] asheappliedforitspatentin1994.Hefoundoutthatthecombination ofthechemicalmakeupofthesurfaceandalsothemicro-andnano-projectionsonthe surfacewerethereasonbehindtheeffect.Theprotrusions [15] ofthelotusleafare 10 μmhigh,witheveryprotrusioncoveredinbumpsofahydrophobic,waxymaterial thatisroughly100nminheight.Thechitinpolymerandepicuticularwaxprojections allowtheleaftotrapair.Waterdropletsrideonthetipsoftheprojectionsandresultina bedofairtomakeasuper-hydrophobicsurface(Fig.2).Scientistsdesignedthisbehavior
Fig.2 Examplesofself-cleaningsurfacesinnatureandtheirSEMimages [16]. (Permissionhasbeen grantedthroughtheCopyrightClearanceCenter’sRightsLinkservice.)
intotheproductLotusan®,aself-cleaningpaint.Thispaintmimicsthemicrostructureof thesurfaceofalotusleafonceitdriesandcureswithintheenvironment.Smallpeaksand valleysonthesurfaceminimizethecontactareaforwateranddirt,keepingthesurface clean.Variousmerchandiseiscurrentlyonthemarketthatmimicsthishydrophobic property,includingconsumergoods,spraycoatings,plungers,toiletfixtures,automotive components,etc.
Researchersatseveraluniversitiesaresynthesizingbiomimeticnanocompositesto formrobustmaterialstobeusedinlightweightarmorsystems,structuresintransportation systems,sturdyelectronics,aerospaceapplications,etc.Naturehasevolvedanadvanced bottom-upapproachforfabricatingnanostructuredmaterialsthathavegreatmechanical strengthandtoughness.Oneofnature’stoughestmaterialsisnacre,whichisbestknown astheiridescentmother-of-pearlmadebymollusks.Mollusksproducenacrebydepositingamorphouscalciumcarbonate(CaCO3)ontoporouslayersofpolysaccharidechitin. Themineralthencrystallizes,producingstacksofCaCO3 thatareseparatedbylayersof organicmaterial.Itsstrengthcomesfromthebrick-likeassembly(interlocked)ofthe molecules [17].
Alizard’sfeetwillbindfirmlytoanysolidsurfaceinashorttime,anddetachwithno apparenteffort(Fig.3).Thisadhesionispurelyphysical,withnochemicalinteraction betweenthefeetandthesurface.Theactiveadhesivelayerofthegecko’sfootisa branchednanoscopiclayerofbristlesknownas“spatula”thatmeasureabout200nm inlength.Severalthousandofthosespatulaeareconnectedtomicron-sized“seta.”Both spatulaeandsetaarefabricatedfromveryflexiblekeratin.Althoughresearchintothefiner detailsofthespatulae’sattachmentanddetachmentmechanismisinprogress,theactual factisthattheyoperatewithnostickychemicals.Itisanimpressivepieceofdesignby MotherNature.Thattheyareself-cleaning,immunetoself-matting(thesetadon’tstick toeachother),anddetachedbydefault(includingfromeachother)areotherinteresting featuresofgeckos’feet [18,20].Theseoptionshavepromptedideasandsuggestionsthat inthefuture,glues,screws,andrivetsmayallbemadebyasinglemethod,castingkeratin orsimilarmaterialintocompletelydifferentmolds.
Magnetotacticbacteriapossesstheextraordinaryabilitytosenseminutemagnetic fields,togetherwiththeEarth’sownmagneticfield,usingtinychainsofnanocrystals knownasmagnetosomes(Fig.4).Thesearegrainssizedbetween30and50nm,made fromeithermagnetite(atypeofironoxide)or,lesscommonly,greghite(aniron-sulfur combo).Severaltypesofmagnetosomesworktogethertoprovideafoldable“compass needle”thatismanytimesmoresensitivethanitsartificialcounterparts.Magnetotactic bacteriaarepond-dwellingandonlyneedtonavigateshortdistances.However,their precisionisincredible.Byvaryingthegrainsize,thesebacteriacanstoreinformation sincethegrowthiscontrolledbythemostmagneticallysensitiveatomicarrangements [22].However,oxygenandsulfurcombinerapidlywithirontoprovidemagnetite, greghite,ormorethan50othercompounds,onlyacoupleofwhicharemagnetic.Hence
Another random document with no related content on Scribd:
nightmare tower
By Jacques Jean Ferrat
Lynne disliked the man from Mars on sight. Yet drawn by forces beyond her control she let him carry her off to the Red Planet.
Anewmagazineshouldbring anewnametosciencefiction —andinthisverynoveland movingstorywebelievewe arelaunchingacareerthat willhelpmake1953 memorable.
[Transcriber's Note: This etext was produced from Fantastic Universe June-July 1953. Extensive research did not uncover any evidence that the U.S. copyright on this publication was renewed.]
Lynne Fenlay had had a few headaches in the course of her twentyfour years. But she had never had a headache like this.
There had been one as a result of her first field-hockey practice at the seminar, when she was twelve and the hard rubber ball caught her squarely above the left eye. There had been another, five years later, when she had used a guided trip to Manhattan during the Christmas holidays to experiment with a bottle of crême de menthe in the unaccustomed solitude of a hotel room. There had been a third as the result of overwork, while she was adjusting to her job with the group-machine.
Each of them had been the result of an easily discovered cause. This headache had come out of nowhere, for no perceptible reason. It showed no signs of going away. Lynne had visited a health-check booth as soon as she could find the time after the discomfort became noticeable. The stamped response on the card had been as disconcerting as it was vague—Psychosomatic.
Lynne looked across the neoplast tabletop at Ray Cornell and wondered with mild malevolence if her fiancé could be responsible for her discomfort. His spoonful of Helthplankton halfway to his mouth, Ray was smiling at something Janet Downes had said. In her self-absorption Lynne had not heard Janet's remark. Knowing Janet as she did, however, she was certain it had undertones of sex.
With his fair height and breadth of shoulder, his tanned good-looking features beneath short-cropped light hair, Ray wore all the outward trademarks of a twelfth-century Viking chief or a twentieth-century football hero. But inside, Lynne thought, he was a Mickey Mouse. His very gentleness, his willingness to adjust, made him easily led.
Lynne forced herself to down another spoonful of Helthplankton and thought it tasted exactly like what it was—an artificial compound composed of sea-creatures, doctored up to taste like cereal.
Mother Weedon looked down at her from the head of the table and said, "What's the matter, Lynne—don't you feel well?"
"I'm all right, Mother Weedon," she said. She felt a pang of fear that stirred the discomfort between her temples. If she were really sick, mentally or physically, Mother Weedon might recommend that she be dropped from the team. After therapy she would be reassigned to some other group—and the thought was insupportable.
"Don't worry about our Lynne." Janet's tone bore a basis of mockery. "She has the stamina of a Messalina."
Damn Janet! Lynne regarded the other third of the team with resentment. Trust her to bring a name like Messalina into it. Even Ray caught the implied meaning and blushed beneath his tan. Mother Weedon looked at Lynne suspiciously.
"Better take things a bit easier," Mother Weedon suggested tolerantly. "After all, the team comes first."
"I know," Lynne said listlessly. She pushed her food away from her and waited sullenly while the others finished theirs. Unable to face the possibility of mental illness, she concentrated on Janet, wondered what the girl was trying to do.
There was always danger of conflict, she supposed, when two young women and a young man were set up as a team. Usually the members were balanced the other way or were all of one sex. But mentally at any rate Lynne and Janet meshed perfectly with Ray. So they had been assigned to live and work together on the groupmachine under Mother Weedon's watchful eye. They had been together now for eleven months.
The trouble with Janet, Lynne thought, was that she wasn't the sort of girl who registered on men at first sight. She was tall, her lack of curves concealed by astute willowiness of movement, her halfhomely face given second-glance allure by a deliberately and suggestively functional use of lips and eyes. Janet was competitively sexy.
Lynne, who was as casually aware of her own blond loveliness as any well-conditioned and comely young woman, had not considered Janet seriously as a rival when she had fallen in love with Ray Cornell. Now, rubbed almost raw by the discomfort of her headache, Lynne decided she had underrated Janet. She was either going to have to get Ray back in line or turn him over to the other third of their team. Either way promised complications for the future....
The three of them walked the thousand meters to the brain-station, avoiding the moving sidewalk strips that would have sped them there in three minutes instead of fifteen. Lynne, who usually enjoyed the stroll through the carefully landscaped urban scenery, found herself resenting its familiarity. Besides, her head still ached.
As they moved past the bazaar-block, halfway to their destination, Lynne found herself wincing at the brightness of the windowdisplays. Usually she found the fluorescent tri-di shows stimulating— but not today. Nor was her mood helped when Janet, nodding toward the plasti-fur coats in one of them said, "I wish I'd lived a century ago, when a girl really had to work to win herself a mink coat."
And Ray replied with a smile she could only interpret as a leer, "You'd have been a right busy little mink yourself, Jan."
Janet gurgled and hugged his other arm and Lynne barely repressed an anti-social impulse to snap, "Shut up!" at both of them.
Lynne wondered what was wrong with her. Surely by this time she ought to be used to Janet's continuous and generally good-humored use of the sex challenge on any male in the vicinity. It hadn't bothered her much until the headache began two days ago. Nor had Ray's good-nature seemed such a weakness. Hitherto she had found it sweet.
On impulse she said, "You two go ahead. I'm going to have a colafizz. Maybe it will knock some of the beast out of me."
"You could stand having a little more of it knocked into you, darling," said Janet. This time Ray said nothing.
Lynne entered a pharmabar and pressed the proper buttons, sipped the stinging-sweet retort-shaped plastitumbler slowly. The mild stimulant relaxed her a little, caused the ache in her head to subside to a dull discomfort. She felt almost human as she took one of the moving strips the rest of the way so as not to be late to work.
Their studioff was situated halfway up the massive four-hundred meter tower of the brain-station. It was shaped like a cylinder cut in half vertically and contained a semicircular table with banks of buttons in front of each seat-niche. The walls were luminous in whatever color or series of colors was keyed to the problem faced by the team. At the moment it was blank, a sort of alabaster-ivory in tone.
Ray and Janet were already in their places. Their conversation ceased abruptly as Lynne entered and slid into her lounger and slipped on the collar that keyed her to the machine. She wondered what Janet had been saying about her, what Ray had been replying.
I'mturningintoaparanoiac, she thought, managed a smile of sorts and said aloud, "What's today's problem?"
"Feel better, honey?" Ray asked her. Lynne nodded.
Janet, obviously uninterested, said, "Disposal of waste-foods so as to be useful to highway construction in Assam—without disruption of traffic-loads in Patagonia."
"Another of those!" said Lynne with a sigh. But she got to work almost automatically, keying her impulses to fit those of Ray and Janet. For the time being personal and emotional problems were laid aside. They were a single unit—a machine that was part of the greater machine—that was in turn part of the administration of Earth. For this work they had been trained and conditioned all their lives.
Early in the century—some fifty years back—when the cybernetic machine had been regulated to their proper functions of recording and assemblage only, of non-mathematical factors, the use of human teams, working as supplements to the machines themselves, had been conceived and formulated by the Earth Government.
No machine, however complex and accurate, could reflect truly the human factors in a problem of social import. For such functions it possessed the fatal weakness of being non-human. Hence the integration of people and atomo-electrical brains. Thanks to their collars the human factors received the replies of the machine-brains through mental impulses instead of on plasti-tape.
By means of the buttons before them they could key their questions to the portion of the machine desired. For specific requests and interkeying with one another they used, respectively, a small throat microphone attached to their collars and direct oral communication.
Janet was the analyst of the team—it was a detail job, a memory job, one which usually went to a woman. And she was good. She culled from the messages given her by the machine those which bore most directly upon the problem.
Assam—vegetarianculture—grainhusksunusedforplasticsbecause of blight-weakness following second A-war—could serve as fifthdepth foundation for second-run non-moving byways.... Patagonia first-line producer of non-weakened grain husks—transportation limited by seasonal deep-frost—atomic heat considered uneconomical for this problem—transportation limited to third-class surfacevehicles—
Ray checked the stream of information selected by Janet. Seek possibility of using synthetic mesh on temporary laydown basis.... Ray was team coordinator, who assembled the facts selected by Janet, put them in shape toward solution of the problem.
Then it was Lynne's turn. In a way, save that all three of them were vital to team-success, she was top-dog. It was up to her to listen to Janet's stream of information, to follow Ray's assembly job, to say,
"This will work," or, "This will not work," or perhaps, "This will work if we do such-and-such, rather than thus-and-so."
There weren't many who could fill this job of synthesizer without too-wide variance from the judgments of the machine itself. Consequently there weren't very many teams actually at work perhaps a score, give or take a few, at any one time. Such synthesization demanded a quality almost akin to intuition—but intuition disciplined and controlled to give results as often as needed.
She concentrated now, though her head was troubling her again, keying her whole being to Janet, then to Ray. And to her horror she began to get a picture—not of the problem of using waste matter to abet highway construction in Assam without disrupting the climatelimited transportation of Patagonia, but of the thoughts and feelings of Janet Downes.
It was frightening to realize that she was reading everything Janet kept carefully concealed behind the sardonic mask of her personality. It was disturbing to discover how much she herself was resented and hated and feared by Janet. It was horrifying to learn how hungry was Janet, how she thirsted to smash Lynne's attachment to Ray, how she planned to use the problem of the headache to discredit Lynne, not only with Mother Weedon and the MindAuthority but with Ray himself.
Imustbegoingcrazy, Lynne thought and became sickeningly aware that she had missed a query from Ray. She turned her attention toward him, found herself enmeshed in a confused jumble of thoughts in which Janet figured with shocking carnality, while she herself was fully clothed and placed on a pedestal resembling a huge and grotesquely ugly frog. Why, she thought, Ray fears me—almost hatesme!
Once again she had lost the thread. Desperately she strove to catch up, found herself issuing an answer. Suggest employment of seatransporttosolveproblem.
Where had that one come from? Lynne wondered. The ocean lanes had not been used for two-thirds of a century, save for fishing and excursions. But hundreds of the old double-hulled cataliners of the pre-atomic air-age were still in their huge cocoon-capsules in various nautical undertakers' parlors.
She watched the large indicator breathlessly, wondering what the machine would answer. Almost certainly a 1.3 variation—which would mean the problem would be shunted to another team. An 0.2 variation was considered normal. Lynne's decisions, over the eleven months of her assignment, had averaged 0.13. Her best mark had been an 0.08.
She caught a flash of Janet's thoughts ... luckySSGso-and-so!She wasn't even paying attention! Rigorously Lynne forced herself to concentrate on the large indicator. It flashed a warning blue, then yellow, then red—and then showed a round single 0!
It was, Lynne thought, impossible. No team had ever, in the entire history of human-cybernetic integration, produced an answer without a single variance with the machine. The best on record was an 0.056 by Yunakazi in East-Asia Center. And he had never come close to it again.
Lynne nodded to the rest of them and unfastened her collar. She felt a little sick to her stomach. An 0-variant answer was supposed to be impossible. But she had attained one, and at a time when her mind had been wandering, thanks not only to her malaise but because of her shocking telepathic experience. She wondered dully if the two factors were integrated in her incredible result.
"... like the monkeys with fifty million typewriters composing a Shakespearean sonnet, probability ultimately favors it," Ray was saying. "Lynne, let's try another. What's the next problem, Jan?"
"Poor reaction of 11th age-group children in Honduras to gnomics during the months of July and August," Janet said promptly. "Wanted—its causes and cure."
Lynne listened in a sort of stupor. When she felt telepathic messages impinging upon her mind she forced them out. She only half-heard Janet's smooth assemblage of facts. Ray's coordination and selection of those most relevant. And then she thought quickly, Climate change to 42per-cent lower humidity, expense contained by use in schoolsonlyandsegregationofchildrenduringcrucialmonths.
Again the flashes from the indicator—again the zero.
Janet regarded Lynne with odd speculation in her hazel eyes, Ray looked a little frightened. Lynne said, "I don't know what's going on but my head is killing me. I'm going home and rest."
"What about our date tonight?" Ray asked quickly—too quickly.
She studied him a long moment. She didlove him, she didwant to marry him, she did want to bear his children—or did she? She was going to have to face the problem squarely and do it soon. She said, "I guess you'd better give me a rain-check, honey."
She walked out the door with a vivid picture of what Janet was thinking. Janet was going to do her damnedest to take Ray away from her that night by the oldest and still the most effective weapon a woman could use. And if Lynne tried to make trouble about it she intended to make trouble for Lynne.
As for Ray—he didn't seem to have any thoughts at all. He was a sort of Thurber male, cowering in his corner while the dominant females fought over him. The only hitch, Lynne decided, was that there wasn't going to be any fight. Janet could have him ... in spades!
She took the moving sidewalk back to Mother Weedon's. For almost a year the trim white dome with its curved polarized picture windows and pink Martian vines had represented home and shelter and a prized individuality after the group-existence of school dormitories.
Now it looked like half an egg of some menacing unearthly bird, half an egg into which she must crawl and hide, unsure of how long it would afford her shelter. Even Mother Weedon, a shrewd and kindly widow of sixty whose strength and good-humor made her the ideal team-matron, looked alien and oddly menacing. She caught the older woman's thoughts as she entered the house. What'shappenedtoLynne?Alwaysthoughtthatgirlwastoobottled up. Sheshouldhave marriedRay sixmonthsago. He'snot thesort of male even a girl as pretty as Lynne can keep on a string indefinitely—notwithaharpylikeJanetinthepicture....
Mechanically Lynne ran her fingers down the magnezipper of her blue plastifleece jacket, deposited it carefully against the magnetic hook on the wall of the entry. She felt a renewed weakness, a sickness that made her head throb more severely than ever. All the way back from the brain-station she had been seeking reassurance in the probability that her sudden telepathic ability was caused by some stimulation of the machine, would vanish when she broke contact with it.
Now she knew better—and her panic increased. She almost ran to the escalator so she wouldn't have to exchange chatter with Mother Weedon. She literally had to be alone.
II
Lynne stirred uneasily on her plastomat. She knew she was there, felt sure she was not asleep. Yet the dream persisted, holding her in a grip that was tighter than reality. She was alone in a strange crystaline chamber, high, high up in a strange crystaline tower. Thanks to the fact there was no metal in its construction, nowhere was there rust. Yet her chamber, like the tower itself, showed definite signs of age and ruin.
An irregular segment of one wall had been penetrated by a missile of some sort and patched with plastic spray to keep out the thin, chill, unending wind. On lower levels, she knew, were larger scars of long-forgotten destruction. Just above the transparent arched ceiling what had been an elaborate tracery of gleaming flying buttresses, their functional purpose long since lost, stood precariously in a pattern of ruin.
Here and there about her, other surviving towers of the city rose in more serious stages of decay. And far below, on the windswept square, huddled the gleaming egg-shaped shelters of the Earthfolk. Beyond the city area the red desert and green oases stippled off to the dark horizon or advanced to invade the steep scarp of the far bank of the great canal.
Lynne was alone in a tower on Mars. Instruments, strange to her eyes but stamped with the familiar patterns of Earthly design and manufacture, lined three walls of the chamber. She knew she should take the downlift and return to the tiny cluster of Earth-dwellings in the court below, that her tour of duty was ended.
Yet she could not leave. Voices whispered within her head and tugged at her emotions, voices whose owners she could not see, whose embodiment lurked ever just beyond the range of her eyes, no matter how quickly she rolled them. Voices that begged for her assistance, offering unheard-of pleasures as a reward, unthought-of torments as punishment for her refusal to cooperate.
They were strange voices, whose message bore the corrupt cynicism of the very old, coupled with the naïve enjoyments of long deferred second childhood—alien voices. Or were they alien? Wasn't it rather that she was the alien, like those other Earthfolk who lived in the cluster of pathetic little huts below, who strove to reclaim the toolean atmosphere of a planet, most of which had long-since escaped into the star-studded black-velvet backdrop of space.
Yes, it was shewho was alien. And with the thought came another, a human picture, so horrible, so gruesome, that her mind refused to
accept it. Yet she knew it was vitally important she see it clearly. But the others, the invisibles, kept derailing her concentration with their whispers of joys unknown before to mortal man or woman, their soft threats of torments beyond those conceived by Dante himself.
"Let us in," they offered softly, with the mischief of the very old. "Let us in and we shall romp and travel and find new uses for your bodies. We shall live side by side within you and lead you to pleasures no souls contained by bodies can ever know. We shall...."
There was something Lynne should ask them, an answer to their Saturnalian bribery—but like their visibility it refused to rise to the upper level of her consciousness. She felt sudden shame at not being able to speak, fear at her inability to marshal needed thoughts, fear that grew quickly into terror while the all-important question struggled vainly to make itself uttered.
Laughing like rollicking imps, the whisperers closed in a hemisphere about and above her, dancing in weird joyous malicious rhythm and bottling up reason as effectively as a plastivial. All at once she found herself holding her head and screaming at them to go away....
Lynne woke up. She discovered herself already sitting erect on the plastomat, supported by hands that dug into its pneumatic surface. She looked wildly around her, noted the familiar tri-di picture of Victoria Falls on the wall, the blank vidarscreen on its stand beside the magnicloset entry, the picwindow with its familiar vista of morning sunlight and greenery outside Mother Weedon's.
Only then did she become aware that her headache was worse. It seemed to grow with each successive morning. During the day it lapsed at times to mere vague discomfort, and with the aid of a couple of syntholaud pills she was able to sleep. But when she awoke each following morning it seemed a trifle worse.
She stepped into the bathostall, which performed all functions of cleansing and elimination simultaneously, felt briefly better and got into sandals, clout and bolero, polarizing them to a gaudy scarlet, which clashed with her fair coloring but expressed her mood of
defiance, not only at her own ailments but the personal treachery of Janet and the waverability of Ray Cornell.
Mother Weedon smiled approval of this gay gesture when Lynne took her place at the breakfast table. "I'm glad you're feeling better, Lynne," she said. "I've been worried about you lately."
"Really putting it on, aren't you, honey?" Janet asked with a trace of resentment. She had polarized her own costume to a soft pink, which was washed out by Lynne's bold color-scheme. Nor could she change it during the day without revealing her defeat.
"Delicious!" exclaimed Ray, ogling her with delight and pouring paprisal instead of sucral on his Helthplankton.
Lynne laughed as she hadn't laughed in days. She wondered why she felt so suddenly light-hearted and happy, especially after her waking nightmare. Then, suddenly, she realised she was utterly unaware of what the others were thinking. She was no longer telepathic. She was normal once more!
However, it required no telepathic powers to sense that Ray was in a sadly shattered state over whatever had happened between Janet and himself on their date the night before. Lynne surmised that her rival had enticed Ray into full courtship, that he was now suffering from remorse, revulsion and a resurgence of desire for herself.
She wondered why she didn't care, then realised that Janet was no longer her rival. Ray was a nice boy, a highly trained and talented boy—but she wasn't in love with him any more. There were, she thought, probably half a billion unattached males in the world at any given moment, many of them far more interesting and attractive than Ray Cornell. All she had to do was look for them....
Headache and nightmare receded further with each mouthful of breakfast she ate. Her appetite was back and she kidded brightly with a miserable Ray and a rather sullen and suspicious Janet all the way to the brain-station. And then things began to happen that shattered her new-found adjustment.
She was barred from entry to the studioff. The electroscreen admitted Ray and Janet as usual but remained an invisible wall that refused her admittance. She was no longer keyed to the groupmachine. Before she could try again a magnovox said, "Please report to Integration Chief on Floor Eighty. Please report to Integration Chief on...."
Ray looked scared. Disruption of a team during working hours was an emotional shock. Even Janet showed traces of fright. But she managed a grin and said, "Give him the old treatment, Lynne, and you can't lose." She accompanied the remark with a thoroughly carnal bump.
Lynne said nothing, being incapable of speech. She turned and made her way to the mobilramp, had a sudden vivid recollection of the older but far more efficient lift on the Martian tower in her dream. She felt sick to her stomach and her headache was thumping again.
She had never been on the eightieth floor before—it was reserved for guiding geniuses, who had no time for mere group-machine members except in case of trouble. Lynne wondered what she had done as she entered a room with walls of soft rolling colors.
The man on the couch, a tall lean saturnine man with dark eyes that seemed to read right through her from out of a long lined white face, didn't leave her long in doubt. He said, "Miss Fenlay, I'm afraid I have bad news for you. As a result of your amazing performance yesterday your usefulness as a group-machine worker is ended."
"But I was right," she protested. "I had the first zero-variation in integration history."
"You needn't be so frightened," he said more gently. "I know this must be a severe emotional shock. You were right—by the machine. We need human factors in cybernetics to show us where the machines are wrong, not where they are right. To come up with two successive zero-variant answers implies some sort of rapport with the machine itself. We can't afford to take further chances."
Lynne sat down abruptly on an empty couch. She felt empty inside, said, "What am I to do?"
The tall dark man's smile was a trifle frosty. He said, "We've been watching you, of course. About all I can tell you, Miss Fenlay, is that your—er aberration is not exactly a surprise."
"You mean you've been spying on me?" Even though Lynne was thoroughly conditioned to accept her life as part of a complex mechano-social integration, she found the idea of being spied upon unpleasant.
"Not really," he told her. "And don't worry. We have no intention of letting your remarkable gifts go to waste." He paused, added, "I hope your headache is better soon."
"Thank you," she said. She was outside before the full implications of his parting shot sank home. How had he or anyone known she was suffering from headache? She had reported it to no one—and the helth-check booth machine was not geared to give confidential evidence or to retain personality keys for checking.
It was a puzzle. She worked on it until she was almost back at Mother Weedon's, then realised the Integration Chief had given her no hint of a new assignment—had only suggested she was to be used. She began to wonder if laboratory test-animals suffered from headaches like the one which seemed to have led to her undoing.
There was no escaping Mother Weedon, who was enjoying a tri-di vidarcast in full view of the front door as Lynne came in. Well, the girl thought, she was going to have to be told anyway—if she hadn't already got the news from the brain-station.
Evidently Mother Weedon had heard. She motioned the girl to sit beside her on her couch and said, "Don't worry, Lynne. You're going to be fine. The trouble with you is you've outgrown your job—yes, and Janet and Ray and me too. You can't help it. You're too good for us and that's that. They'll be moving you on."
"But I likeit here," cried Lynne. "I like you and Jan and Ray and our work with the group-machine. I don't want it to change."
"But it will—everything changes," said Mother Weedon gently. "I'm glad you've been happy here. But your happiness has meant Janet's unhappiness and, more lately, Ray's."
"I—see," Lynne said slowly. She hadn't thought of things in that light before. But of course it was true. The first real home she had ever known was about to be taken from her and the experience was too personal to allow much detached thinking.
Like most genetically-controlled children whose double-birth had been successful, she had been brought up with functional rather than sentimental care. Not having known her parents, not having known her twin brother on Mars, she had never missed them. The teachers and matrons at the seminary had been carefully selected for their warmth and competence. There had always been plenty of playmates, plenty of interesting things to learn.
Living at Mother Weedon's had been a new and emotionally opening experience, as had the blossoming of her romance with Ray Cornell, her now-fractured friendship with Janet Downes. It was not going to be easy to leave, to tear up only recently established roots, to set down new ones which might in time be as ruthlessly sundered.
She felt frightened and very much alone, as if she were again in the Martian tower of her nightmare with only alien and disembodied voices speaking to her. Mars—she wondered a little about it. Somewhere on Mars was her twin, Revere Fenlay, the brother she could not remember. She wondered if he too were having troubles. There were stories floating about of twins whose rapport spanned lifetimes separated by the distance between the planets. But she knew nothing of Mars.
She watched a vidarcast with Mother Weedon, an unreal historical romance of love and adventure in one of the vast sprawling industrial empires of the mid-twentieth century. There was, for twenty-second-century folk, a vast emotional appeal in the job-
competition, the hard compulsory physical toil, the dangers of that exciting era. But Lynne was too wrapped up in her own problem to react as usual.
While she and Mother Weedon were lunching on pineapple soup and Bermudasteak with shadbacon and lacticola, Ray and Janet came in. They pretended concern at what had happened to Lynne and the team but were obviously excited with one another and the prospect of integrating a new member of the team in Lynne's place.
After the meal Janet and Lynne were briefly alone in the vidaroom. Janet eyed Lynne covertly and Lynne said, "It's all right, Jan. I'm not going to put up a fight for Ray. Under the circumstances it's only fair. I don't know what's going to happen to me and you and him—"
"Damn you, Lynne Fenlay!" Janet's sudden flare of hot emotion was almost frightening. "You wouldbe like this. Don't you realise that by being noble you'll leave both of us with a guilt complex we'll never be able to shake?"
"Sorry," said Lynne sincerely. "I can't help it."
Janet regarded her narrowly, shook her head. "Hasn't anything ever touched you, Lynne?" she asked. "Haven't you ever wanted Ray or anyone as I want him? Haven't you ever hated anyone as I'm beginning to hate you? Haven't you ever been human?"
"Jan!" Lynne was shocked, then vaguely frightened. "I don't know I guess maybe not," she said. "But Jan, I can't help it. That's the way I am."
Janet sighed and said, "In that case I'm sorry for you." She changed the subject quickly as Ray came wandering in, gave Lynne an unhappy look, then crossed the room and turned on the vidarscreen. Peace of an uneasy sort reigned for the next hour.
"When are they assigning your new member?" Lynne asked as the picture, a documentary about solar heat, came to an end.
"Not for a day or so," said Ray. He looked at her piteously. "We— we're going to miss you, Lynne. I wish I understood...."
"You're going to be too busy," Lynne told him. "And don't worry about me, Ray. I've already talked to Jan."
"You mean you're not angry about us?"
Lynne shook her head, glanced at Janet, was again startled by the blazing hatred that was beamed her way. She wondered what it must feel like to hate in such thorough fashion. She was relieved when she heard Mother Weedon talking to someone at the door.
A moment later the widow entered and said, "This is Rolf Marcein, kids. He's going to be staying with us a little while." She introduced the three of them to the newcomer.
Lynne barely acknowledged the greeting. She was too startled. The most recent addition to Mother Weedon's charmed circle appeared, in the semi-dark room, to be the man who had given her her walking papers that morning on the eightieth floor of the brain-station tower. He was tall, dark, lanky, saturnine. His name was Marcein. At least that was something Lynne hadn't known before. And then she noticed that this Marcein's face was not so pale, that his eyes were brighter, his manner and movements more athletically poised than the man on the eightieth floor. Mother Weedon pressed the polarizer to let more light into the room, since the vidarbox was not on. The stranger's tan, seen in the light, was startling, especially to Lynne, who had seen his pale double so recently.
His double—that meant his twin, she thought. And if his twin worked in the brain-station, then thisman must be a Martian. Certainly that would account for his tan, caused by living under the thin atmosphere of the red planet as it would account for an athletic poise acquired during the hardships of Martian existence. You'reright,ofcourse.IamDolf'stwinandIamfromMars.
It took her almost a full second to realise the thoughts had not been spoken. She was telepathic again, aware not only of the newcomer's thoughts but of those of the others in the room—though not as much aware of theirs as of Rolf Marcein's.
She looked at him with something like panic, saw his brilliant dark eyes upon her, noted that he wore his clothes well, that there was something almost lupine in his grace, something almost overpowering....
You must know you're beautiful yourself, Lynne Fenlay—if soft and unawakened.IhaveanideaIcouldturnthetrick....
It was like a blow. Not only could she read his thoughts, Lynne realised—but he could read hers. She felt her face flame and a sudden surge of resentment toward his arrogance that forced her to leave the room lest she reveal the weakness it caused. And as she left his soft laughter rang like hailstones in her ears.
III
The days that followed Rolf Marcein's arrival at Mother Weedon's became, to Lynne, a period of waiting. It was a period of waiting games as well. No summons came from the eightieth floor of the brain-station to give her a clue as to the nature of her next assignment. For the first time in her life she found herself hung in a vacuum with nothing definite to do or to look forward to.
Naturally she wondered whether Rolf Marcein might not be the answer to this facet of her problem. But not even her growing telepathic abilities could pry a response out of his mind. He seemed to be visiting the home planet on the vaguest sort of business— something to do with development and transport of specially-bred plant and animal stock for the red planet.
It seemed absurd on the face of it that such an obviously able adjustee should be returned to Earth on such a mission, especially with every gram of interplanetary ship-space at a premium. Yet either it was truth or Rolf had developed some method of screening his thoughts against telepathic probing—a frightening idea in itself.
He hung around Mother Weedon's most of the time. As a result Lynne saw a lot of him throughout the days and evenings, a fact which both pleased and alarmed her unreasonably. It was during the third night of his stay that he invaded, or tried to invade, her nights as well.
Before drifting off to sleep she found herself dwelling on him with relaxed reverie. Ray and Janet had had some sort of quarrel and the atmosphere that evening had been far from pleasant. It was a relief to lie alone, to let her thoughts roam and quest as they would.
Rolf had talked of Mars during a stroll to the bazaar-mart during the afternoon. He had described a boar-hunt on Earth's sister-planet during a night when both Deimos and Phobos were describing their rapid orbits across the cloudless sky.
The pig, as man's most adaptable food-animal, had been the first livestock imported to Mars less than three decades earlier. Now, according to Rolf, the animals had in large measure reverted to their feral state and constituted a menace to man and his works alike.
"We used flashlights and small-arms paralyzers on that hunt," Rolf said. "We flushed a whole herd of them in an erosion-gully along the border of the Great Southern Canal—didn't get so much as a smell of the brutes until we were right on top of them.
"At that we managed to nab a baker's dozen for de-tusking and redomestication. Ferkab, it was touch and go for a bit! One big brute slipped under my ray and if I hadn't been lucky enough to jam my flashlight tube into his mouth he'd have taken my leg off."
"What does ferkab mean?" Lynne asked, a little annoyed at feeling an atavistic thrill from the account of the primitive hunt.
To her delight Rolf actually blushed beneath his tan. He began with, "I don't think you'd appreciate its meaning," then recalled her telepathic powers and shut up and blushed more deeply.
At which it had been Lynne's turn to feel her face grow hot. The meaning of ferkab, an approximate translation of certain graphically illustrated ancient Martian runes, was explicit to the point of bawdiness. Yet on Mars, apparently, it was used in mixed company.
So, lying half asleep, Lynne not surprisingly visualised the boar hunt as Rolf had described it. She could see his weatherproof aluminum clothing gleaming in the pale light of the swift tiny moons, shining in the occasional ray of a flashlight as he and his shadowy companions worked their way along the eroded bank of the canal.
Then the sudden rustle and thump and grunting of the beasts as they came charging out of their threatened shelter, their vast menacing shapes with huge tusks and little red eyes glittering in the confused crisscross of flashlight rays. She saw the paralyzers' brief glow, heard the thud of falling animal bodies, saw the sudden rush of one furious beast inside the protective sweep of Rolf's handweapon, saw his quick graceful evasive movement, heard the champ of savage tusks crushing the hard alloy of the metal tube.
Once, on the vidarscreen, she had watched a toreador do his dance of death with a furious bull, in an historical show. Rolf, she thought, was slim as a toreador, slim and graceful and equally accustomed to facing danger and death as an accepted part of life.
Then, she told herself scornfully, she was reverting to the primitive as if she were a Martian sow herself. She thought of the word ferkab and what it meant and felt her face grow hot in the darkness. For she could visualise Rolf and—herself—in a way she had never been able to think of herself with Ray Cornell.
It's not confined toMars, darling, came the sudden probe of Rolf's thought over hers. ButittakesaMartiantobethebest.
Reverie was obliterated by rage. She sent back a string of thoughts that should have blistered Rolf's brains—if he had any decency. He withdrew before her counterattack and she wondered if he really did have any decency—or if her rage were all she had pretended.
She was cool to him the next day and the arrival of the new member of the group-machine gave her opportunity to avoid him. Her replacement was a dark stocky quiet young man named Alan Waters and he seemed quite smitten with her—a fact which made Janet visibly jealous. Lynne found herself quite enjoying her triumph.
But the day after, when the other three reported for work at the brain-station and Mother Weedon visited the bazaar-mart for some needed household supplies, Lynne found herself looking at a mischievously contrite Rolf across the breakfast table.
He said, "I'm sorry if I've offended you, Lynne. Apparently I made the mistake of thinking you had blood in your veins."
Lynne acted without volition for the first time since early babyhood. She picked up the plastisaucer in front of her and flung it across the neoplast tabletop at him. He ducked and for a moment his dark eyes blazed with laughter and then he sensed her distress and helped her with the atocleaner.
She tried to apologize but the words refused to come. And he never mentioned the incident afterward. Instead he took her for a walk through the park and talked to her of the more feral beauties of his own planet. "It's far wilder than this," he told her, gesturing at the neat clusters of trees and flowers, the perfectly clipped hedges about them. "Wilder and deadlier and far more beautiful."
"This is perfection," she told him.
"And perfection is death," was his reply.
"I thought Mars pretty much a dead planet," she said.
"It's a vast mausoleum," he said, his eyes lighting. "A mausoleum visited by new life, a mausoleum in which the very souls of the dead themselves seem beginning to stir. It's raw new life burgeoning on the old."
He talked on and she felt the beginnings of small responses stir within her and frighten her. For she had been conditioned to Earth and to wish for Mars was wrong. Finally he stopped and faced her and captured both her hands in his incredibly strong ones.
"Lynne," he said. "I haven't much longer here. I want to take you back home with me. Will you come?"
"Home—on Mars?" she countered. The idea was impossible. Yet, somewhere within herself, she wanted to go. Then the reasons, the millions of reasons why she couldn't say yes, came flooding up within her. Surely Rolf knew them—or did he?
"You know the system and the reasons behind it," she reminded him. "You have a twin right here in the city. I've talked to him—it was he who gave me my walking papers from the group-machine."
"He told me," said Rolf quietly. "He told me a lot about you. Enough so I wanted to see you and get to know you. Now that I do know you I want you to go back with me. Can't you see, darling? There's little use for telepaths on Earth. On Mars we need them desperately. I think I can arrange a transfer."
"But my brother is already there," she told him a little desperately. "I —we—they can't leave two of us on one planet. And what right have I to ask him to come to Earth? He's not conditioned."
"But maybe he'd like to come back," Rolf suggested. "Maybe he's not happy on Mars."
"It's not just that," she said miserably. Nor was it. For the first time the entire system by which the Mars project was functioning seemed to her vastly unfair. Until that moment she had accepted it, considered it as immutable as the need for the sun itself.
The Earth Government, which was what the U.N. had evolved into after its first tortured half-century of birth, was determined not to repeat upon alien planets the mistakes of imperialism and colonization that had caused the home planet all but to tear itself to pieces during the twentieth century.
No convicts, no misfits, no refugee cultists were to be sent out to settle the newly-opened red planet—instead, the cream of Earth's best trained, most gifted and strongest young men and women were to do the preliminary settling. For it would still be many years before the arid world would be able to support much humanity.
There had been protests—chief among them a group of eugenicists who felt that loss of such a large group of qualified young folk would cost the home planet more genetically and socially than it could afford. The answer had been genetically-induced twins on the part of parents qualified to pass a wide variety of mental, physical and psychiatric tests, open to all who wished to join the project.
One of each set of such induced identical twins was early selected to go to Mars, the other to remain on Earth. Thus Earth lost nothing, yet had its potential Martians, ready for conditioning and training in special seminaries for lifetime work on the red planet. When one of a pair of twins was a girl, the other a boy, the boy was the one sent out—since life on Mars was still a rugged affair. Thus it was that Lynne had been reared for an Earth-career while her brother, Revere, had been educated and coached for a Mars-life.
Lynne's entire twenty-four years had been passed for the purpose of integration into and work for the improvement of humanity on her native planet. The very idea of Mars was terrifying, as was the idea of traveling there through space. She simply couldn't endure the wrench of the trip, the separation from all that mattered.
Rolf stood there quietly, letting her thoughts flow without interruption. Then he said, "I see—but it's not as bad as all that, darling. After all, Imade the trip in reverse."
"But that's different—you're a man!" she protested.
"Nor is being a man as bad as you seem to think," he said and she sensed that he was teasing her and was grateful for the change in mood. Before she realized what she was doing she called him mentally a thoroughly bawdy Martian word.
"Where did you learn that?" he asked, startled.
"Where do you think?" she countered—and enjoyed seeing him blush again. They had a pleasantly innocuous time together the remainder of that day and evening.
The following morning Lynne awoke from another horrible nightmare of alien worlds to find her headache back in full force. So bad was it, in fact, that after making a half-hearted effort to get up she fell back on her plastomat, actually moaning a little. She felt as if she were undergoing some long-forgotten sort of Inquisition torture.
Rolf walked into her room within the hour and so sick was Lynne that she didn't even protest his presence. He said, "Lynne, darling, you've got to get over this. Believe it or not you're killing me."
"Then stay in your own mind." She managed a whisper of a smile.
"You're like a bad tooth," he said inelegantly. "You know it's going to hurt if you touch it but you can't stop running your tongue over it."
"Oh, shut up," she said rudely. "So now I'm an ulcerated tooth. I've never had one so I wouldn't know."
"Nor have I," he replied promptly. "But I've read about them. Come on. I'm going to take you to Centromed and get you fixed up."
"I'm too ill to move," she quavered, alarmed at the prospect.
But he simply moved in and took over, virtually forcing Lynne firmly but gently into her clothes, getting her downstairs and onto a
